STATISTICAL TECHNIQUES FOR ASSESSMENT OF INLAND WATER QUALITY

Abstract: Complex water quality of Lake was assessed with Multivariate statistical techniques during the 2-year (2011-13) monitoring program. Cluster analysis grouped whole lake into three zones. Discriminant Analysis (DA) calculated three parameters Dissolved Oxygen (DO), Chlorophyll a (chl a) and Total Suspended Solids (TSS) to 100 % correct assignment in the spatial analysis of the three clusters in stepwise mode and 91.7 % in standard mode, whereas in temporal analysis, DA calculated six parameters (DO, Chl-a, TSS, transparency, air temperature and water temperature) to 100 % correct assignment in both standard and stepwise modes. The Principal component analysis (PCA) assisted to extract and recognize the factors responsible for water quality variations in four seasons of the year. Principal components (PCs) captured more than 60 % of the total variance in each season. Strong loadings included DO, TSS, Available phosphorous (avail. P), total phosphorus (TP), temperature, ammonia-N and nitrate-N. The natural parameters (temperature and DO), the inorganic parameter (TSS) and the organic nutrients (Avail P, TP, nitrate-N and ammonia-N) were the most significant parameters contributing to water quality variations in all seasons, and indicate organic and sediment pollution in the lake